"Everything Server crashes when multiple clients reconnect"
* In index.ts
- added a variable to hold the initialize timeout
- store the timeout in the oninitialized handler
- clear the timeout in the cleanup callback
* In roots.ts
- In the catch block of syncRoots, log the error to the console via .error rather than attempting to send to the client because the most probable case here is that we don't have a connection.
* In simulate-research-query.ts
- remove redundant local variable in getTask
* Everywhere else, prettier.
- Use params.task instead of params._meta.task for task metadata
- Remove pollInterval from task requests (only available on result)
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Implement graceful degradation for elicitation on HTTP transport:
- STDIO: Full elicitation works via sendRequest
- HTTP: Catches elicitation failure, uses default interpretation
- Task completes successfully on both transports
simulate-research-query now uses try-catch around sendRequest and
includes explanatory message when elicitation is skipped on HTTP.
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Instead of waiting for the client to call tasks/result to trigger
elicitation, the server now sends elicitation/create directly from
the background process using sendRequest. This simplifies the flow:
- Server sends elicitation proactively when clarification is needed
- Client receives and handles it via existing elicitation handler
- Task resumes and completes after receiving the response
- Client's polling sees completed status
This approach avoids requiring the client to detect input_required
status and call tasks/result as a side-channel.
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Add tools that demonstrate bidirectional MCP tasks where the server
sends requests to the client for async execution:
- trigger-sampling-request-async: Send sampling request with task
params, client creates task and executes LLM call in background,
server polls for completion and retrieves result
- trigger-elicitation-request-async: Same pattern for user input,
useful when user may take time to fill out forms
Both tools:
- Check client capabilities (tasks.requests.sampling/elicitation)
- Accept both CreateTaskResult and direct result responses
- Poll tasks/get for status updates
- Fetch final result via tasks/result
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
- Add tasks capability with list, cancel, and requests.tools.call
- Add InMemoryTaskStore and InMemoryTaskMessageQueue from SDK experimental
- Add simulate-research-query tool demonstrating task lifecycle
- Task demonstrates working -> input_required -> completed status flow
- Uses elicitation for ambiguous queries when client supports it
Closes#3037🦉 Generated with [Claude Code](https://claude.ai/code)
The syncRoots call should be idempotent, requesting roots if they haven't been yet for the session, but always retuning the cached roots otherwise. That could be deferred but setting the handler for roots_list changed note should not.
* In server/roots.ts
- only set the notification handler and call for initial roots list if the roots aren't already cached for this client.
* In server/index.ts
- in the oninitialized handler
- get the sessionId from the transport
- set a 350ms timeout to call syncRoots with the server and sessionId
- this delay cause it to run after the `notifications/initialized` handler finishes, otherwise, the request gets lost.
* All other changes attributable to prettier
* In server/roots.ts
- in syncRoots, if roots are supported fetch them
* In get-roots-list.ts,
- Don't import and inspect current roots map, just call syncRoots to get the list.
* In how-it-works.md,
- added a section on conditional tool registration
* In server/index.ts
- import registerConditionalTools
- in an oninitialized handler for the server, call registerConditionalTools
- removed clientConnected from ServerFactoryResponse and all mentions in docs
* In tools/index.ts
- export a registerConditionalTools function
- refactor/move calls to registerGetRootsListTool, registerTriggerElicitationRequestTool, and registerTriggerSamplingRequestTool out of registerTools and into registerConditionalTools
* In server/roots.ts
- only act if client supports roots
- remove setInterval from call to requestRoots. It isn't happening during the initialze handshake anymore, so it doesn't interfere with that process if called immediaately
* In get-roots-list.ts, trigger-elicitation-request.ts, and trigger-sampling-request.ts,
- only register tool if client supports capability
* Throughout the rest of the files, removing all references to `clientConnected`
* In get-roots-list.ts, query the server's cache of the latest roots from the client and only request the list from the client if it doesn't exist.
* In roots.ts, export the roots map
* In get-roots-list.ts, query the server's cache of the latest roots from the client and only request the list from the client if it doesn't exist.
* In roots.ts, export the roots map
Adding Trigger Elicitation Request and Get Roots List tools
* Updated architecture.md
* Added roots.ts
- tracks roots by sessionId
- setRootsListChangedHandler
- listens for roots changed notification from the client
- updates the roots map by sessionId
- sends log notification or error to the client
* In server/index.ts
- import setRootsListChangedHandler
- in clientConnected callback
- call setRootsListChangedHandler passing server and sessionId
* In sse.ts, stdio.ts, and streamableHttp.ts
- receive clientConnected from server factory
- call clientConnected when server is connected to transport
* Added get-roots-list.ts
- registerGetRootsListTool
- Registers the 'get-roots-list' tool with the given MCP server.
* Added trigger-elicitation-request.ts
- registerTriggerElicitationRequestTool
- registered tool sends an elicitation request that exercises all supported field types
* In tools/index.ts
- imports registerTriggerElicitationRequestTool and registerGetRootsListTool
- in registerTools
- call registerTriggerElicitationRequestTool and registerGetRootsListTool, passing server
* Updated architecture.md
* Refactor/renamed get-sampling-request.ts to trigger-sampling-request.ts
- use trigger instead of get throughout
* In tools/index.ts
- sorted display order
[WIP] Adding Gzip File as Resource tool
* Updated architecture.md
* Added gzip-file-as-resource.ts
- imports getSessionResourceURI and registerSessionResource from session.ts
- exports registerGZipFileAsResourceTool
- the registered tool
- validates the input URI
- fetches the file safely
- compresses it
- creates and registers the resource
- returns resource or resource link
* In tools/index.ts
- import registerGZipFileAsResourceTool
- in registerTools,
- call registerGZipFileAsResourceTool passing server
* Added resources/session.ts
- getSessionResourceURI gets a uri to the specified name
- registerSessionResource registers the session-scoped resource and returns a resource link
For tools where we seek to get some response from the server, renamed as an action, e.g., "Get Sum" rather than "Add" or "Get Annotated Message" rather than "Annotated Message", so that it's clear what the intent of the tool is in a quick review.
* Updated architecture.md
* Refactor/renamed add.ts to get-sum.ts
* Refactor/renamed annotated-message.ts to get-annotated-message.ts
* In tools/index.ts
- sorted presentation order
Adding get-structured-content tool
* Updated architecture.md
* added get-structured-content.ts
- Registers the 'get-structured-content' tool with the provided McpServer instance.
- The registered tool processes incoming arguments using a predefined input schema,
generates structured content with weather information including temperature,
conditions, and humidity, and returns both backward-compatible content blocks
and structured content in the response.
Adding the get-resource-reference and get-resource-reference tools
* Updated architecture.md
* Added get-resource-links.ts
- Registers the 'get-resource-reference' tool with the provided McpServer instance.
- The registered tool retrieves a specified number of resource links and their metadata.
* In get-resource-reference.ts
- fixed tool description
* In tools/index.ts
- import registerGetResourceLinksTool
- in registerTool
- call registerGetResourceLinksTool
Adding the get-resource-reference tool
* Updated architecture.md
* In prompts/resource.ts
- Refactor/extracted the prompt argument completers into exported functions in resources/templates.ts
- Refactor/extracted BLOB_TYPE, TEXT_TYPE, and resourceTypes into exported constants in resources/templates.ts as RESOURCE_TYPE_BLOB, RESOURCE_TYPE_TEXT, and RESOURCE_TYPES
- In resources/templates.ts
- refactor renamed index to resourceId throughout for consistency with prompts and tool references
* Added tools/get-resource-reference.ts
- Registers the 'get-resource-reference' tool with the provided McpServer instance.
- uses enum and number schema for tools to provide resourceType and resourceId arguments. Completables don't work for tool arguments.
- Returns the corresponding dynamic resource
* In tools/index.ts
- imported registerGetResourceReferenceTool
- in registerTools
- called registerGetResourceReferenceTool
Adding the annotated message tool
* Updated architecture.md
* Added annotated-message.ts
- registers a tool that returns a message with annotations on different content types
* In package.json
- updated TS SDK version
Added print-env, and sampling-request tools
* Updated architecture.md
* In tools/index.ts
- import registerPrintEnvTool and registerSamplingRequestTool
- in registerTools
- call registerPrintEnvTool and registerSamplingRequestTool
* Added tools/print-env.ts
- registers a tool that takes no args and returns the environment variables
* Added tools/sampling-request
- registers a tool that
- takes prompt and maxTokens args
- sends client a sampling request
- returns the client response in the result
